Optimize Task._wakeup
Optimize Task._wakeup

Part of PR #289.

vxgmichel/asyncio,ajdavis/asyncio,Martiusweb/asyncio,vxgmichel/asyncio,ajdavis/asyncio,Martiusweb/asyncio,vxgmichel/asyncio,ajdavis/asyncio,Martiusweb/asyncio